Many food related businesses are involved in these diversion efforts. More than 250 are included in the composting collection programs, more than 600 donate food and over 2,000 are served by rendering collections. Diversion results are estimated as follows: Nearly 3,000 tons/year (tpy) of edible food, including almost 700 tons of edible produce; more than 23,000 tpy through animal feed (including rendering); and over 12,000 tpy through all composting collections (and that is expected to continue to grow).
The City and County of San Francisco Recycling Program (the city) places a high priority on recycling a large portion of the organic waste stream, especially food residuals, in meeting the city’s diversion goals. A waste composition study in 1996 estimated that there were 127,000 tons of commercial organics, including almost 65,000 tons of food (18 percent of disposed waste), being landfilled. To increase organics recycling, the city has provided assistance in developing or expanding many of the above programs, including funding for equipment, outreach and technical assistance in their implementation.
EXPANDING SOURCE SEPARATED COLLECTION
The San Francisco Food Bank started collection of unsold edible produce in May, 1996 from 25 wholesalers at the San Francisco Produce Terminal, and has since expanded to other wholesalers/distributors in the city. Participating businesses benefit from the program by reducing their garbage costs and claiming tax deductions for donated food. The Food Bank sorts the edible from the nonedible produce with mostly volunteer labor. More than 70 percent of the produce collected is delivered to large kitchen operations that feed thousands of people daily in San Francisco. The sorted nonedible produce is collected by a dairy farmer from Sonoma County, who blends it into his dairy and heifer feed as well as sells the material to other farmers in the area. The Food Bank has collected and diverted more than 1,300 tons of produce from San Francisco in the last two years, and is now diverting produce at a rate of almost 700 tons/year. Of this amount, more than 500 tons were redistributed as edible food and almost 200 tons went for dairy and cattle feed.
In August, 1996, Sunset Scavenger Company (Sunset) started collecting source separated spoiled produce that the Food Bank did not want from 25 wholesalers at the produce terminal for composting at the Richmond Sanitary Composting Facility nearby in the East Bay. Each participating business was provided with a dedicated green bin for source separating vegetative food discards. This material was picked up with a front loading packer and delivered to the Richmond facility. The compost operator demonstrated good windrow management and improved product quality by processing this organic material along with other yard trimmings received. The product was marketed primarily to landscapers.
Sunset has expanded its collection throughout the city, except for the downtown area served by Golden Gate Disposal and Recycling Company (Golden Gate), serving many types of food generators, including other wholesalers, large supermarkets (including Safeway), produce markets, juice bars, restaurants, caterers and floral/plant shops. By the end of 1998, participation in this program had grown to 177 businesses, more than doubling the number in that year. The materials collected also have expanded to include waxed cardboard, a significant item for most of the participating businesses. This program expansion has been facilitated by an outreach contractor (through the city) providing training, monitoring and follow-up to participating businesses and by staff hired by Sunset to conduct outreach and coordinate service to bring on new participating businesses.
Instead of going directly to the composting site, a change was made to take collected materials to the city transfer station that are load them into transfer trailers and hauled by Sanitary Fill Company (Sanitary Fill). Since the summer of 1998, materials have been sent to the B&J Sanitary Composting Facility (B&J) in Vacaville, owned by Norcal Waste Systems, also the parent company of Sunset, Golden Gate and Sanitary Fill. (Commercial organics from the city’s program are no longer going to the Richmond Sanitary site.) B&J had received a permit to process all food material including pre and postconsumer residuals. It has been utilizing the Ag-Bag method, a static aerated plastic bag system for composting the organics from San Francisco along with locally collected yard trimmings.
The composting program has been funded through the garbage rates at an estimated cost of $135/ton, including collection, transfer, haul and compost facility tipping fees, outreach and training. As an incentive to participate, businesses pay 25 percent less for produce collection than for garbage collection and thereby reduce their overall disposal costs when they can sufficiently reduce their garbage quantities and corresponding service levels. Sunset collected more than 6,000 tons in 1998, doubling the monthly average during that year. The company has set a goal of diverting at least 10,500 tons through its composting collection program and has recently started to add collection of all food (pre and postconsumer) for food service customers.
ALL FOOD COMPOSTING COLLECTION
Golden Gate collects four tons/day, seven days/week of source separated all food material from 30 markets and restaurants in the city’s Chinatown, North Beach and Fisherman’s Wharf areas. This was an old swill collection route that Golden Gate inherited from a hog farmer who had been collecting from these businesses everyday for years and bringing it to his hog farm in the Central Valley near Lodi. When the farmer went out of business, he offered it to Golden Gate, which saw it as a great opportunity to get into the food recycling arena, provided the company could find a market for it. After exploring other market options, Golden Gate eventually was able to bring it to B&J, once the facility had received its permit to compost all food material. Participating businesses pay less for this service than they do for garbage. Golden Gate may not expand this particular collection given the option it has developed below which reduces its cost.
REROUTED MIXED ORGANICS COMPOSTING COLLECTION
In the spring of 1998, Golden Gate started to experiment with implementing a rerouted downtown collection of targeted high volume produce generators (primarily produce markets) for composting. The hauler initially did some curb sorting to remove the larger nonorganic material during the rerouted collection. The mixed material (mostly organics with visible plastic and other nonorganic material) was transferred to B&J for inspection and test processing. The mixed material was composted with source separated organics in the aerated bag process. The operator was able to remove the nonorganic physical contaminants (mostly plastic) by trommel screening the composted material. This material has been acceptable to B&J, although it prefers the cleaner, source separated material.
Since Golden Gate does not receive additional rate funding for recycling programs (unlike Sunset), the company has chosen to pursue this different collection approach. With a rerouted mixed organics collection, participating businesses do not need to source separate. Therefore, the hauler doesn’t need to offer a financial incentive to participants (which would have resulted in a revenue loss for Golden Gate). The rerouted collections expanded to include a route of 30 produce markets and a route of 12 restaurants by the end of 1998, diverting 15 to 17 tons/day, seven days/week. These collections are expected to continue to expand. By the end of 1998, Golden Gate was diverting at a rate of more than 5,800 tpy for its combined source separated all food and rerouted mixed organics collection. By Jack Macy.